If you are interested in this topic, don’t scan — be sure to read through Martin’s entire story. In particular, note: Solar cells are now improved and have pushed ‘windows’ to the top of the pyramid. Martin says that replacing windows is “unlikely to be cost effective” overall. He does points out:

In a heating climate, the installation of low-e storm windows is more cost-effective than installing new replacement windows.

Windows are a big interest of mine — as in, I’m in the camp working to counter the greedy marketing onslaught that wants people to replace perfectly good windows with new windows today. I will say, in addition to the overall concern that such replacements are not environmentally/energy -justifiable, I tend to believe our old, slow-growth-wood windows will last much longer than many of the windows being built today. Another reason to go slow if and think this one through if you are contemplating the window-replacement issue. Martin has more advice on windows on his blog, and does the site he blogs on, Green Building Advisor. Lots of homework required on this big-ticket-expenditure, if you want to do it for whatever reason. Note: Old windows may have been painted with lead paint and there may be other concerns; get your own properly licensed professional to assess what you have and to make informed decisions. For more info and links see our Be Safe/Renovate Safe page.

Also see Martin’s story, Stupid Energy Savings Tips, in which he debunks numerous claims made by the ill-informed all over the internets.

Also please note: Martin’s story has been updated — although the Pyramid has not — to reflect improvements in photovoltaic / solar technology. I’m not sure I see where Martin would put PV’s on the pyramid now… but lower, it seems. Even so, I think a key point of this whole thing is not to get too juiced too fast about “sexy solar cells” as some sort of be all end all fixit silver bullet. There seem to be many more, very boring but very effective issues you can tend to first — and it sounds like the key is to get assessments first, then build a plan.

Comments

Do explore alternatives to vinyl replacement windows. There are wood options available, if you must replace, as well as metal choices that are better made than the first-generation aluminum windows.

Quite aside from the health issues presented by vinyl, these windows are made to last only 15-20 years–and that’s if the seal on the double panes doesn’t pop sooner (causing fogging and frost) or the plastic hardware doesn’t break.

Lead paint is not a reason to discard a window. It is a reason to invest in safe, proper window restoration.

I love this article on window restoration too, though the work he’s doing looks really intense and having bought a house with crappy replacement windows, I won’t be actually using it anyway. But still enjoyed.

Living in Phoenix, we have more of a heat issue than cold. Removable Shade Screens on our single paned windows are very efficient in our 6 months of summer and triple digits. I would almost say necessary on our 1963 home

Great article. Since we moved into our house (actually, even before), we’ve steadily been working our way up the pyramid. We’ve pretty much got everything except the top three set. I keep looking at solar electric and the cost keeps coming down but it definitely isn’t there yet in terms of return on investment. Windows are definitely an even harder one to justify.

Pam, you are so right about the windows. My house’s 1954 windows were replaced shortly before my purchase in 1999. By 2009 nearly all those windows had warped to some degree, the southern exposure ones to the point where I had to replace them in 2010 and 2013.

One solution to single pane wood windows that are fixed style is to install a 2nd pane of glass a 3/8 inch or so in the same casing. It forms that great important air pocket needed .
We have these on all of our fixed windows and they are much less expensive than replacement of the original wood type. You cannot see the difference.It is best appreciated in the winter.!

It is impossible to really insultate well unless you also consider the window coverings. Even with state of the insulated windows you can still save 50% more with the right window covering. That too is a pyramid. Insulting the walls is a start. Insulting the window type, then adding the right window covering.